Hoya filters are excellent, and if you go to their website, you will find that the HMC (Hoya Multi Coated) series are a step up from the "standard" range. It is very easy to pay more than this for a standard filter, so shop around for the HMC level, which reduces the reflection given by the glass.
The visual effect given by a UV filter is very subtle but still clearly visible, especially in sunny landscape shots. They certainly never seem to have an adverse effect, and so are ideal to leave on a lens permanently as a means of protection. If you want to really visibly enhance your outdoor shots, go for a polarising filter, which can be fitted on top of this if you want to, although this might lead to some vignetting on wide angle shots due to the combined length of the rings.
Overall, excellent and convenient lens protection at a very reasonable price.